HPE GreenLake Administration
Operating System - HP-UX
1833883
Members
1831
Online
110063
Solutions
Forums
Categories
Company
Local Language
back
Forums
Discussions
Forums
- Data Protection and Retention
- Entry Storage Systems
- Legacy
- Midrange and Enterprise Storage
- Storage Networking
- HPE Nimble Storage
Discussions
Forums
Discussions
Discussions
Discussions
Forums
Discussions
back
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
- BladeSystem Infrastructure and Application Solutions
- Appliance Servers
- Alpha Servers
- BackOffice Products
- Internet Products
- HPE 9000 and HPE e3000 Servers
- Networking
- Netservers
- Secure OS Software for Linux
- Server Management (Insight Manager 7)
- Windows Server 2003
- Operating System - Tru64 Unix
- ProLiant Deployment and Provisioning
- Linux-Based Community / Regional
- Microsoft System Center Integration
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Discussion Boards
Blogs
Information
Community
Resources
Community Language
Language
Forums
Blogs
Go to solution
Topic Options
- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Printer Friendly Page
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
06-07-2001 06:36 PM
06-07-2001 06:36 PM
Several processes establish mapping between process?? address space and a file via mmap() with MAP_SHARED selected. Whether subsequent references to the share region are mapped directly to related processes or indirectly via the disk I/O ?
Solved! Go to Solution.
2 REPLIES 2
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
06-08-2001 11:03 AM
06-08-2001 11:03 AM
Solution
anyone who MAP_SHAREDs a file will all share the same memory. given the peculularities of PA-RISC processors and their caches, it is important to let mmap() decide where to make the association. there should be more about that in the manpage.
i also believe that the FS works to keep things up-to-date with others doing stuff to the same file via file I/O, but my personal suggestion is to not mix one process using mmap() with another doing read/write to the same file. it just "feels" like it would be fraught with issues to me, but i'm just a raving paranoid :)
i also believe that the FS works to keep things up-to-date with others doing stuff to the same file via file I/O, but my personal suggestion is to not mix one process using mmap() with another doing read/write to the same file. it just "feels" like it would be fraught with issues to me, but i'm just a raving paranoid :)
there is no rest for the wicked yet the virtuous have no pillows
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
06-09-2001 06:16 AM
06-09-2001 06:16 AM
Re: mmap
The VMM maps the I/O buffers from the kernel directly into the address space of the process when you use mmap(). Any changes to the buffers would therefore be "seen" immediately in the processes that mmap() the file, regardless of how the changes are made; ie: through a memory reference or through write().
As a general programming practice, I would avoind mixing the two access methods, as it would be very confusing to anyone trying to decipher your code.
As a general programming practice, I would avoind mixing the two access methods, as it would be very confusing to anyone trying to decipher your code.
No matter where you go, there you are.
The opinions expressed above are the personal opinions of the authors, not of Hewlett Packard Enterprise. By using this site, you accept the Terms of Use and Rules of Participation.
Company
Events and news
Customer resources
© Copyright 2025 Hewlett Packard Enterprise Development LP